Topological insulators are materials with astonishing properties: Electric current flows only along their surfaces or edges, whereas the interior of the material behaves as an insulator. In 2007, Professor Laurens Molenkamp at Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany, was the first to experimentally demonstrate the existence of such topological states. His team achieved this seminal work with quantum wells based on mercury and tellurium (HgTe). Since then, these novel materials have been the hope for a fundamentally new generation of components that, for example, promise innovations for information technology.
Source:
https://phys.org/news/2019-10-topological-nanoelectronics.html